6420947 has 4 divisors (see below), whose sum is σ = 6914880. Its totient is φ = 5927016.

The previous prime is 6420913. The next prime is 6420959. The reversal of 6420947 is 7490246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6420947 - 2²⁰ = 5372371 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6420907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 246947 + ... + 246972.

It is an arithmetic number, because the mean of its divisors is an integer number (1728720).

Almost surely, 2^6420947 is an apocalyptic number.

6420947 is a deficient number, since it is larger than the sum of its proper divisors (493933).

6420947 is a wasteful number, since it uses less digits than its factorization.

6420947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493932.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 6420947 is about 2533.9587605168. The cubic root of 6420947 is about 185.8658897606.

The spelling of 6420947 in words is "six million, four hundred twenty thousand, nine hundred forty-seven".